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Title: High-Cycle Fatigue Properties of Notched Specimens for Ti-6Al-4V ELI Alloy at Cryogenic Temperatures

Abstract

The notch effects on the high-cycle fatigue properties of Ti-6Al-4V ELI alloy have been investigated at cryogenic temperatures. Smooth and notched specimens with the Kt=1.5, Kt=2 and Kt=3 were prepared. High-cycle fatigue tests were carried out at 4, 77 and 293 K. One million cycles fatigue strength (FS) of smooth specimen was increased with a decrease of the test temperature. Although the FS of each notched specimen at 4 K were lower than those of 77 K. Fatigue crack initiation sites of the smooth, the Kt=1.5 and the Kt=2 notched specimens at 4 K were facets in the specimen interior (internal type fracture) and those of the Kt=3 notched specimens were at the notch root (surface type fracture). The size of individual facets comprising the internal fatigue crack initiation sites correspond to almost the {alpha}-grain size. Therefore, improvement of the fatigue strength of the notched specimens for Ti-6Al-4V ELI alloy which show internal type fracture at cryogenic temperatures requires attaining a smaller area size by grain refining.

Authors:
; ;  [1]
  1. National Institute for Materials Science, Tsukuba, Ibaraki, 305-0047 (Japan)
Publication Date:
OSTI Identifier:
20800165
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 824; Journal Issue: 1; Conference: Cryogenic engineering conference, Keystone, CO (United States), 29 Aug - 2 Sep 2005; Other Information: DOI: 10.1063/1.2192347; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ALUMINIUM ALLOYS; CRACKS; CRYOGENICS; FATIGUE; FRACTURES; GRAIN SIZE; NOTCHES; TESTING; TITANIUM ALLOYS; VANADIUM ALLOYS

Citation Formats

Yuri, T., Ono, Y., and Ogata, T.. High-Cycle Fatigue Properties of Notched Specimens for Ti-6Al-4V ELI Alloy at Cryogenic Temperatures. United States: N. p., 2006. Web. doi:10.1063/1.2192347.
Yuri, T., Ono, Y., & Ogata, T.. High-Cycle Fatigue Properties of Notched Specimens for Ti-6Al-4V ELI Alloy at Cryogenic Temperatures. United States. doi:10.1063/1.2192347.
Yuri, T., Ono, Y., and Ogata, T.. Fri . "High-Cycle Fatigue Properties of Notched Specimens for Ti-6Al-4V ELI Alloy at Cryogenic Temperatures". United States. doi:10.1063/1.2192347.
@article{osti_20800165,
title = {High-Cycle Fatigue Properties of Notched Specimens for Ti-6Al-4V ELI Alloy at Cryogenic Temperatures},
author = {Yuri, T. and Ono, Y. and Ogata, T.},
abstractNote = {The notch effects on the high-cycle fatigue properties of Ti-6Al-4V ELI alloy have been investigated at cryogenic temperatures. Smooth and notched specimens with the Kt=1.5, Kt=2 and Kt=3 were prepared. High-cycle fatigue tests were carried out at 4, 77 and 293 K. One million cycles fatigue strength (FS) of smooth specimen was increased with a decrease of the test temperature. Although the FS of each notched specimen at 4 K were lower than those of 77 K. Fatigue crack initiation sites of the smooth, the Kt=1.5 and the Kt=2 notched specimens at 4 K were facets in the specimen interior (internal type fracture) and those of the Kt=3 notched specimens were at the notch root (surface type fracture). The size of individual facets comprising the internal fatigue crack initiation sites correspond to almost the {alpha}-grain size. Therefore, improvement of the fatigue strength of the notched specimens for Ti-6Al-4V ELI alloy which show internal type fracture at cryogenic temperatures requires attaining a smaller area size by grain refining.},
doi = {10.1063/1.2192347},
journal = {AIP Conference Proceedings},
number = 1,
volume = 824,
place = {United States},
year = {Fri Mar 31 00:00:00 EST 2006},
month = {Fri Mar 31 00:00:00 EST 2006}
}
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